Maintenance time for the 392. Will 3 in 1 oil damage the seals? Gun oil? Thanks

ATF for pumpers

link here, probably available to you locally.
I use this oil for the pumpers and it does look like ATF, not sure though.
3-1 oil and compressed air are the combo to "Diesel" in the chamber and resulting pressures may damage the rifle so I keep it simple and get the right stuff.
A little tube will last quite a while.

30w oil also works, but if you want the good stuff, call Tim @ Mac1. His Secret Sauce is the stuff for all pumpers. Been using the stuff for years now on my 2 Steroid 392's and Crosman pumpers, zero wear and the valve is happy! If not use what you got. And all you need is a couple of drops at all pivot points. Do not put oil in the air hole. The oil will migrate down the pump arm and into the valve after a few shots. When you open the bolt you'll notice oil in the breech.

Thanks for all replies.
I'll get the good stuff for next time.

I use 30W non detergent motor oil. I've read that the dertergents can harm seals.